A couple of common combinatorics question solutions in C#

C# Combinatorics

public static List<List<T>> GeneratePowerSet<T>(List<T> list)
{
    var result = new List<List<T>>();
    if (list.Count > 0)
    {
        foreach (var t in GeneratePowerSet(list.GetRange(1, list.Count - 1)))
        {
            result.Add(t);
            var temp = DeepCopy(t);
            temp.Add(list[0]);
            result.Add(temp);
        }
    }
    else
    {
        result.Add(new List<T>());
    }
    return result;
}

public static List<List<T>> GenerateAllKCombinations<T>(List<T> list, int k)
{
    var result = new List<List<T>>();
    if (k > 0)
    {
        for (int i = 0; i < list.Count - k + 1; i++)
        {
            var t = list[i];
            var temp = DeepCopy(list);
            temp.RemoveRange(0, i + 1);
            var tempResult = GenerateAllKCombinations(temp, k - 1);
            foreach (var tempItem in tempResult)
            {
                tempItem.Add(t);
                result.Add(tempItem);
            }
        }
    }
    else
    {
        result.Add(new List<T>());
    }
    return result;
}

private static List<T> DeepCopy<T>(List<T> t)
{   
    var temp = new T[t.Count];
    t.CopyTo(temp);
    return temp.ToList<T>();
}